如何使用反射设置用户定义类型的值？

Question

I have a type

type SpecialString *string

I have two reflect values, aVal and bVal (just to be clear aVal and bVal are of type reflect.Value) where

aVal.Type() // *SpecialString
bVal.Type() // *string

In regular code I can create c, a pointer to a special string like so:

a := "foo"
b := SpecialString(&a)
c := &b   

How can I achieve the same using reflection?

aval.Set(bVal) // does not work: "reflect.Set: value of type *string is not assignable to type *SpecialString"

Answer 1

You need to convert the types and pay attention to what you can and cannot set. Something like:

type SpecialString string
var s string = "source regular string"
var ss SpecialString
// Get the reflect.Value of the thing &ss pointing at.
ssv := reflect.ValueOf(&ss).Elem() 
// You need to convert string to SpecialString explicitly
ssv.Set(reflect.ValueOf(s).Convert(ssv.Type())) 
fmt.Printf("ss = %T %+#v
", ss, ss)

https://play.golang.org/p/OtFuS5bAaax